


The Under-Arm Vulnerability

by heyselene



Series: Vulnerability [1]
Category: Supernatural
Genre: Anal Sex, Bottom Castiel (Supernatural), Bottom Castiel/Top Dean Winchester, Communication, Fluff, M/M, Smut, Top Dean Winchester, cas has a hyrdoflask, this essentially makes cas a vsco girl
Language: English
Status: Completed
Published: 2020-06-11
Updated: 2020-06-11
Packaged: 2021-03-04 06:34:05
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 2,286
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/24669205
Author URL: https://archiveofourown.org/users/heyselene/pseuds/heyselene
Summary: It's all about showing some vulnerability, which has never come easily for Dean. It's addictive to watch Castiel allow it, though. Wherein Dean is an indulgent lover and he wonders whether he'll ever be able to let go in the same way that Cas does.
Relationships: Castiel/Dean Winchester
Series: Vulnerability [1]
Series URL: https://archiveofourown.org/series/1783906
Comments: 4
Kudos: 66





	The Under-Arm Vulnerability

**Author's Note:**

> Oh hi, this is the first thing I've ever posted. I've been in the fandom and reading fanfic for like, my entire life, but I finally decided to start posting them, LOL! Here you go :,)
> 
> I don't really.... edit? I apologize, lol. Please be gentle! This is all for fun.
> 
> Before writing: I am writing this because I couldn't get this idea out of my head.

They're almost there. On their way to a crescendo. Dean's hands are wrapped around Castiel's thighs, holding his legs up and wide so he can dig his nails in tight.

Castiel is thrusting up against him to meet his downward strokes, and Dean knows that he needs to get the angle just right, work his hips in just the right slow-roll-snap that will make their skin slap together and have Castiel begging for him.

Castiel has long since given up making their sex life something that has to be all prim and perfect. He falls apart on Dean every time he bottoms now— not just moaning and rolling his eyes back— but truly letting his body thrash, his hips jerk and his lips tremble.

It's a little different on the receiving end, Castiel can let give all of the ropes over to his body and let himself just move in time with Dean's hands and hips.

They both know Dean has a hard time letting go when the roles are reversed. It's helpful for Dean to watch Cas in this position— vulnerable and open, eyes bleary, and gone on the endorphins. Maybe someday Dean will feel more comfortable with being in the same position.

For now, topping is a good break from trying to let his guard down.

Dean has the upper hand. He can study Cas carefully, control the speed, the weight, the angle of his thrusts, and the pressure of his fingernails along Cas' ribs. He can make sure Cas is okay too— watch his reactions for any sign of discomfort or frustration. From the top, Dean can focus on making sure Cas reaches his orgasm like falling: weightless and floaty and rushing for as long as Castiel can handle it. Sometimes longer than he can, if Dean has him pinned the right way. Not some half-hearted head-spin from a handjob, or a quickly swallowed blow-down-the-throat (though Dean loves that too).

Dean hooks his hand on Cas' thigh just under his knee. He angles Cas' hips up so that he can get his hips just under— a little higher— there. Dean eases back and uses his other hand to scratch down Cas' left nipple harshly. He digs in his nail and then does his best to tease it with his thumb and forefinger, pulling a gentle moan from Cas.

Castiel's hands are on Dean's hips, his fingernails digging in and giving Dean that pain-pleasure wires crossed sensation that he has been jerking off to since he was a teenager.

Dean waits until he is eased back, and Cas' body is positioned just right. Dean uses the leverage of pressing the fronts of his thighs to the bed to prepare and snakes his left hand from Cas' nipple. It slides to where his cock is sitting, red and hot and wet— veering to the left and resting against his stomach in a way that makes him appear so debauched and vulnerable that Dean has to remind himself to keep it together.

Dean stills his hips for the first few strokes to Cas's cock, mostly to reacclimate him to the touch so he doesn't startle when Dean finally pushes him over the edge.

Dean gives gentle pumps at the base of him, watching Cas' eyes flutter.

"Dean," Cas breathes, his hands petting against his hips still. Cas allows one hand to reach down to his own balls, and Dean gives the movement an affirming nod. He watches as Cas touches himself without embarrassment, rolling his balls with one hand

Dean slowly gives a half thrust, and Cas sucks in air, "Fuck."

Dean's hand moves quicker on Cas' dick. He works further up it and twists some at the head now, just the way Cas likes it, where he's a little slicker and the head catches.

Dean lets his thrusts get deeper, picking up speed and seeing that Cas is live-wire strung out. Cas is almost too close to coming for Dean to make this orgasm one of those explosive, dingo-ate-my-baby-crazy orgasms.

Castiel must be right there with him because he starts to ease his hips in time with Dean's and Dean picks up speed. He twists his left hand in time with the final five or six snap-drags of his hips. He can feel Cas meeting him in the middle, his breath caught as he whimpers and whines and — oh fuck—

Cas' dick sprays across his stomach and through Dean's fingers as Dean jerks and twists Cas through what looks like a wild orgasm.

Cas makes those delirious little moans and his hips are twitching because he can't handle keeping up with Dean's rhythm. So Dean gets up on the flat of his feet, almost on his toes so he can get enough leverage to fuck Cas into the bed with the weight of his body, hopefully plowing directly into the sweetest spot.

Cas groans at the feeling and takes it all in, his body trembling.

And because Dean is an over-indulgent lover, and knows exactly what buttons push Cas into a writhing mess, he presses his palm to the head of Cas' softening cock and grinds down onto it.

Cas' voice starts to raise with little "oh!"s and "shit!"s and Dean grins at that.

Cas is reaching down to grab Dean's wrist so Dean drops Cas' thigh and gathers both of Cas' hands in his own to hold them in a bruising grip. Cas doesn't really need to be held down, the indication of pulling his hands away was enough. But Dean presses Cas's hands down to his chest, effectively immobilizing him as his other hand works Cas's cock and his hips continue to snap against Cas' thighs.

Dean switches to rapidly jerking Cas to give him a moment's break before going back to brute pressure on the very sensitive tip—

(Cas is trying to squirm away because of the overstimulation, but Dean knows how strung out this makes Cas, how it leaves his mind blank and his body floaty all over. Dean has half a mind to tie Cas up to the bed frame and touch him until he is begging Dean to stop.)

Cas is letting out quiet, shuttering sobs and squirming left to right when Dean finally lets up. both on Cas' dick and his restraint. Dean comes lazily into the condom he's wearing and thrusts through it quickly. Dean doesn't indulge himself in this— Cas is already too over-sensitive and floaty to be making decisions about what hurts and whether Dean should stay inside him right now.

So Dean pulls out and ties the condom and tosses it to the hardwood floor.

He scoops his hands around Cas' sweaty lower back and gently hefts him up the bed so that Cas' head is resting on one of their feather pillows. Dean climbs up between Cas' still twitching thighs and lets his weight slowly melt down onto Cas. He pins him down so he's warm and grounded and surrounded by the smell-feel of Dean's skin.

Cas rubs his wet eyes against his shoulders and tries to even out his breathing. Once Dean is on him, he is put back together enough to pull Dean by his shoulders into a sloppy kiss that's wet with Cas' tears and saliva.

Dean knows that the tears are from crazy over-stimulation and the floaty space that Cas is in right now, but he still checks,  
"You okay, baby?"

Cas, oddly, blushes and hides his face in Dean's neck. Usually, Cas is so blunt and unembarrassed, so Dean has to remind himself that he just fucked Cas into the bed while holding down his wrists.

"Words Cas. You have to use words," Dean says gruffly, nosing at the side of Cas' head to get him to speak.

"I'm better than okay, Dean," Cas' gravelly voice sounds against Dean's throat.

"Good," Dean says, his arms gently petting against Cas' rib cage. 

Dean wonders if he'll ever be able to get strung out like Cas does after sex. He's seen it happen to loads of women in his time, but it was never something on the table for him during those encounters. Sure, maybe for a moment when he was coming, or afterward for a minute while she was just being the little spoon, but it wasn't like this floaty echo-y feel-good thing that Cas has introduced him to. Hell, Dean didn't think it was something that guys were supposed to want until Cas became addicted to it, asking Dean to get him there.

Not that Dean doesn't like getting Cas to that spot because, yeah, it's totally fucking addicting to see Cas lose his shit like that, coming so hard he can't speak and just giving in to what Dean tells him to do.

Dean supposes that if he let himself show a bit more vulnerability, if he just asked Castiel or fingered himself open one day and just kneeled on the floor, Cas would give him what he wanted without a second thought.

Dean thinks maybe his inability to ask for it is part of it— he wants Cas to haul him into bed and tie his hands too tight and fuck Dean a little dry and maybe smack him when he's about to orgasm.

But Dean knows he won't get that with Cas unless he asks for it— Castiel's love for Dean may still make Dean's head reel, but he understands now that Cas would never do anything he thought would hurt Dean.

Cas finally starts to come back to himself and squirm when he can feel the come drying between their stomachs.

To Dean's credit, the last time he got up to get a washcloth after they fucked, Cas had been all teary-eyed and upset when he had gotten back and it had broken Dean's heart.

Cas makes a humming noise and then laughs throatily when Dean presses his face into the pillow to try and get out of getting up.

Cas regains his bearings and rolls so they're side to side, noses inches apart and legs tangled.

He stretches his arms out and rolls his shoulders, his eyes bright and bleary, his hair making him look the best type of fucked-out.

Dean is so fucking in love.

Cas leans forward to lick— yes, lick— along Dean's lips before climbing up over Dean and shoving Dean's hips so he is on his back, with Cas perched over him like a cat.

Dean eyes him warily, his protective instinct still aware that Cas is vulnerable in more ways than one right now. Cas settles to sit on Dean's hips, and slowly presses his lips along Dean's chest, licking frequently like he's trying different spots for their taste.

Cas makes it to the spot where Dean got some of Cas' come smeared and Cas licks it up, even though it's bound to be cool and sticky now.

Cas slides his fingers down Dean's ribs languidly and Dean shivers, so Cas copies the movements but digs his nails in this time, causing Dean to let out a little moan.

Cas has that proud after sex smirk and hair as he kisses up Dean's chest, and then noses his way into Dean's armpit, stopping there to breathe in deeply.

Dean pulls his elbows up to give Cas better access. As weird as this would feel normally, Cas is definitely too spacey to care, and Dean can't help himself but give Cas whatever he wants.

Whenever Dean thinks about things like this after, he clams up and gets all pink in the cheeks.

But Dean is fucking sensitive under his arms, and when his arms are bared like that it makes him feel helpless to Cas in the best way.

Cas noses and then kisses and then licks and sucks at the taste and scent of Dean's fresh sweat and grime, probably salty in his mouth.

The feeling makes Dean's cock try to kick back up against his stomach and Dean can't help but grind it a little against Cas' hip. There's no way either of them are getting off again tonight, and they both know that. It still feels kind of nice to simply touch, even after the fact.

Cas gives a firm bite to both Dean's nipples on his way to Dean's other armpit.

When Cas has finished, Dean is sad and happy at the same time: missing the feeling but happy that the vulnerable moment is passing. He tucks his arms around Cas and hauls them up to chest to chest, using his foot to kick the sheet at the end of the bed up towards them. He wraps the sheet around their naked bodies to hide them from the rest of the world.

Cas is content and comfortable, now more back to himself, but still a little hazy with all of the good shit that just went down. His mouth tastes like sweet come and sweat, so he licks his lips and cuddles into Dean's chest.

In a few minutes, Dean will get up to refill Cas' stupid hydro flask with the bee stickers so they can both get in at least a few ounces of water before bed. He'll probably wash off a little too, and grab some wipes for Cas too. Dean didn't think tonight was rougher than usual, but he'll check with Cas again, and maybe take a peek just to make sure that his angel isn't down-playing some discomfort.

Dean will get back into bed and they might talk for a couple of minutes, but mostly they'll settle so Cas can run his hand through Dean's hair sleepily until they both finally pass out.

It's a good fucking life.

FIN.

**Author's Note:**

> I just finished writing it: ok what the fuck that was just supposed to be about my newly discovered armpit licking kink... ;(
> 
> There's a part 2! With bottom!Dean... Just so you know


End file.
